Internal Seminar: Po-Shun Chuang, PhD Student, Marine Biophysics Unit

Internal Seminar

Speaker: Po-Shun Chuang, PhD Student, Marine Biophysics Unit (Satoshi Mitarai Unit)

Title: Coral polyp bail-out: A stress response and possible application

Abstract: 

Coral reef ecosystems are important in both economic and ecological aspects. Comprising less than 1% of the global ocean floor, these ecosystems host a comparably high biodiversity and productivity, which make them valuable fishery spots and tourist attraction for the human society. However, corals in the world are now subjected to a variety of stresses due to the global climate change. Coral bleaching, defined as the dissociation of coral and the symbiotic algae living inside of its cells, is the most common physiological response of corals under stress. In addition to that, some reef-building corals also display another stress response, which is characterized by the detachment of free-living coral polyps from the skeleton. Although in 1982 this phenomenon was specifically examined and named “polyp bail-out”, it was somehow ignored in the trend of coral studies until these recent years. Given that this detachment response shows a very distinct strategy from bleaching in facing to environmental changes, a better understanding of this phenomenon is necessary. In this project I therefore aim to make a survey of this stress response in different corals. Preliminary results of this survey show that polyp bail-out can be induced in most coral species in the Pocilloporidae by an increasing seawater salinity, a stress simulates strong evaporation in the wild. In the second stage of this project, the solitary polyps obtained from polyp bail-out will be settled in a microfluidic device to allow real-time microscopic observation. Quantitative experiments will then be conducted on the scale of single polyp. By comparing the results to colony-scale data we will then be able to attempt the discussion of emergent property in corals from polyp to colony. Since there are relatively few studies on this phenomenon so far, this project is expected to open a new field for future coral studies.

Please join us after the seminar for free pizza, soft drinks, and scientific discussion!